After reading a little further into the impacts of animal waste on the water quality I have come across something that as a geologist has a particular interest to me.

The impact of animal waste on groundwater. This is a topic that I didn't see much material on whilst researching water pollution. However, I have recently uncovered this paper by D C Gooddy et al. from 2001. This study looks into the impacts of cattle slurry on such groundwater stores in the UK.

UK aquifer location and levels. Source BGS

The groundwater in the UK predominantly comes from three aquifers; the Permo-triassic sandstone, the jurassic limestone and the chalk formations (GroundwaterUK). These aquifers supply 25%, 15% and 60% respectively.

With a total abstraction of 2400 million meters cubed per year from groundwater sources in England, for industry agricultural and domestic use - the UK definitely has a significant dependence on groundwater as a source of freshwater - right?

So, if these repertoires of water are slowly being polluted that is a severe problem for the entire country. However, the concern about livestock pollution hasn't seemed to have cause for concern!

There are estimated to be over eleven hundred slurry pits in England and Wales (Nicholson & Brewer 1997) many of which could potentially be sitting above the aforementioned aquifers.

The study be DC Gooddy et al. highlighted the ease of which pollutants can leach through fractures in the chalk lithology to depths of 15 meters below the surface.

However, due to strict regulations in the UK regarding the lining and earth baking beneath slurry pits the impacts on potable water were seen to be negligible. Nevertheless, in countries or states with less strict regulations the outcome may not be as trivial - food for thought considering groundwater is the source of drinking water for 99% of the rural American population (Estimated use of water in the USA 2000) and the EPA don't think it necessary to regulate the water standards of private drinking wells - of which 13.5 million American households depend.

Groundwater pump in the USA. source: waterEducation